<html>
<head>
    <title>Welcome!</title>
    <script src="/js/jquery-1.12.4.js"></script>
    <script src="/js/jquery-1.12.4-my.js"></script>
</head>
<body>
<form action="/login" method="get">
    用户名:<input type="text" id="name" name="name" value="jack">
    密码:<input type="text" name="password">
    <input type="submit" value="登陆">
</form>


<button type="button">Click me</button>
<script type="text/javascript">
    $(document).ready(function () {
        $("button").click(function () {
            $("#name").val("jack2");

            console.log($("#name").val());
            console.log(jq("#name").val());
        });
    });
</script>
</body>
</html>